Role of urea in the preparation of highly porous nanocomposite aerogels

被引：40

作者：

Casula, Maria F.

Loche, Danilo

Marras, Sergio

Paschina, Giorgio

Corrias, Anna

机构：

[1] Univ Cagliari, Dipartimento Sci Chim, I-09042 Cagliari, Italy

[2] Univ Cagliari, INSTM, I-09042 Cagliari, Italy

来源：

LANGMUIR | 2007年 / 23卷 / 07期

关键词：

D O I：

10.1021/la0635799

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The preparation of highly porous CoFe2O4-SiO2 nanocomposite aerogels was successfully achieved by a novel sol-gel procedure involving urea-assisted co-gelation of the precursor phases. This method allows fast gelation, giving rise to an aerogel with 97% porosity. The formation of CoFe2O4 nanocrystals homogeneously distributed within the matrix occurs after calcination at 750 degrees C and is complete at 900 degrees C. Despite the high temperature required for the formation of the CoFe2O4 nanocrystals, the high porosity typical of aerogels is still retained.

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收藏

页码：3509 / 3512

页数：4

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